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"But you can't get out more or even equal to what you put in in terms of energy content. There have to be some losses along the way, especially if a steam cycle is involved. I'm wondering what the energy balance looks like for the whole plant. That is, for a BTU out contained in a hydrocarbon product, how much went in to produce it?"

Of course not--but by getting the fuel into a source that can be used directly in fuel cells, the MUCH higher conversion efficiency of the fuel cell more than compensates for those losses. It is the efficiency of the TOTAL CYCLE that counts---not just the efficiency of the gasification process vs. combustion.

And in fact, for central power usage, coal gasification/fuel cells is an even BETTER combination, as what is called the "solid oxide fuel cell" can eat BOTH the hydrogen AND the carbon monoxide.

It is the use of the fuel cell in the total conversion process that makes major gains in efficiency possible.

There is value in looking at the individual stages of the process, as that allows you to identify the potential targets for technology enhancements that improve the overall process. Most people today focus on the end use, especially in the transport sector. The entire process from extraction-transport-processing-transport-end use has to be examined at each stage. We all know that crude oil refining is an energy-intensive step, so it is valid to look at the gasification process in a similar light.

I understand the advantage in the fuel cell replacement of the IC. It avoids the combustion step at the end use and that has environmental advantages, as its probably better to deal with fog than smog. But surely the gasification process is not without its share of effluents. You mentioned the slag. I'm wondering if airborne releases also occur. In conventional refining there is always some waste gas produced that is flared off. I've been around some refineries that were pretty smelly. Would a coal gasification plant present a similar environmental impact?

Again, I'm just running down the questions that might arise if a national effort were made in this direction. Trading impacts from oil refineries for those from gasification may not be a bad bargain if it helps us in other ways, like reduced dependence on imported energy, or more economical fuels.